Fig. 1. Targeted mutagenesis of the 3' UTR of the Otx2 gene. (A) The targeting vector is shown in third line; fourth line illustrates recombined locus; first and last lines show EcoRI fragments (11 and 7.5 kb) detected by Southern blot using probes (a-e, white boxes) external to the targeting vector or within neomycin gene. Kp, KpnI; Ap ApaI; E, EcoRI; met, methionine; stop, stop codon; pA: polyadenylation signal. (B) Southern blot analysis of one targeted cell line (Otx2
/+) and wild-type HM-1 ES cells hybridised with probe b in A. (C) PCR genotyping of a litter from two heterozygotes using the primers indicated as filled and open arrowheads in A. (D) In situ hybridisation of an Otx2/Otx2 embryo at 10 d.p.c. with the Otx2-specific probe (probe d in A).
